A pick and carry crane is a type of crane that is able to move (i.e. travel) while it has a load suspended from a boom of the crane. Some pick and carry cranes are able to drive on public roads at highway speeds, with these cranes being classified as special purpose vehicles. The design of pick and carry cranes can vary depending on the application of the crane. Some designs of pick and carry cranes are more manoeuvrable compared to other crane types. For example, when the pick and carry crane is articulated, the whole crane can fit within a turning circle of the crane. This design feature can enable articulated pick and carry cranes to be used in tight or confined spaces to lift and move loads, such as on the floor of a manufacturing facility.
Pick and carry cranes can also take the form of “taxi cranes”, which is a reference to the crane travelling with all equipment required to operate through the full range of capability of the crane. In some taxi cranes, the same operator station is used to control the crane when travelling (such as on a public road) as when operating the crane at a facility. This “single cabin” arrangement helps to simplify crane configuration, and also provides flexibility for the operator (i.e. by not having to move back and forth between a driver's cab and a crane cab). Many cranes cannot operate as a taxi crane since they cannot transport all components required to operate, hence support vehicles are generally required to carry extra components, such as counterweights and rigging including slings & hooks.
As the maximum rated capacity (MRC) of the crane increases, its weight generally increases. Pick and carry cranes tend to carry lighter loads in comparison to other cranes (i.e. less than 25 tonnes). However, the increased manoeuvrability of pick and carry cranes has led to a demand for pick and carry cranes that are able to carry more than or that have an MRC greater than 25 tonnes, whilst also being able to lift and carry such larger loads in confined or tight spaces.
However, as the rated capacity of a pick and carry crane increases, its susceptibility to sideways tipping generally also increases. The increase in susceptibility to sideways tipping comes about since there are physical limitations to the overall width of a pick and carry crane when e.g. driving on public roads such as highways or when driving in a facility. Crane tipping and thus crane toppling presents occupational as well as public health and safety issues.
With mobile cranes, for example, outriggers can be used to minimise susceptibility to sideways tipping. However, such outriggers are used when the crane is operating at a stationary position. Because pick and carry cranes need to travel with a load, this means that outriggers typically cannot be used.
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